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Status of Imagery
Standards in TC211
26 November 2014
C Douglas O’Brien - Canada
Liping Di - USA
Jianya Gong - China
Wenxiu Gao - China
Wolfgang Kresse - Germany
Imagery, Gridded and
Coverage Data
 Imagery and gridded data is the dominant form of
geographic information.
 This has led to the development of a number of standards
that are well used for the storage, encoding, manipulation
and exchange of geographic imagery, gridded and coverage
data – from satellite imagery to undersea bathymetry to
elevation grids.
 ISO TC211 has developed 8 standards, Technical
Specifications, and Technical Reports and has 2 new
standards and one revision in work.
Standards Development
Published standards
ISO/TR 19120:2001 Geographic information - Functional standards
ISO 19101-2:2008 Geographic information - Preference model - Part 2: Imagery
ISO 19115-2:2009 Geographic information - Metadata - Part 2: Extensions for imagery and gridded data
ISO/TS 19129:2009 Geographic information - Imagery, gridded and coverage data framework
ISO/TS 19130:2010 Geographic information - Imagery sensor models for geopositioning
ISO/TS 19130-2 Geographic information - Imagery sensor models for geopositioning - Part 2: SAR, InSAR,
lidar and sonar
ISO/TS 19139-2:2012 Geographic information - Metadata - XML Schema Implementation - Part 2 :
Extensions for imagery and gridded data
ISO/TS 19159-1 Geographic information - Calibration and validation of remote sensing imagery sensors Part 1: Optical sensor
Under preparation
WI 19159-2 Geographic information - Calibration and validation of remote sensing imagery sensors - Part 1:
Lidar
WI 19130-1 Geographic information - Imagery sensor models for geopositioning (Revision of ISO/TS
19130:2010)
WI 19163 Geographic information - Content components and encoding rules for imagery and gridded data
Related
ISO 19123:2005 Geographic information -- Schema for coverage geometry and functions
What is Imagery?
 Most people are familiar with the images they get from their
cameras or cell phones. They have a sense that pixels are the
little dots that make up an image and that the number of
megapixels in an image determines how sharp the image is.
This seems simple.
 Beyond the initial apparent simplicity
imagery gets much more complex.
Coverages and Metadata
 There are 2 areas of complexity:
 Metadata; and
 Coverage geometry.
 Extensive metadata is needed to describe remote sensing
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


imagery. This is addressed in several of the TC211 standards.
In addition coverage geometry views imagery and other
similar types of data as mathematical fields that can
manipulated and transformed.
The basic coverage geometry is addressed in ISO 19123 Schema for coverage geometry and functions.
The framework that links the coverage geometry and
metadata is addressed in ISO 19129 - Imagery, gridded and
coverage data framework.
The overall structure is defined in ISO 19101-2 – Reference
Model Part 2 Imagery
Coverages Concept
 An image is not just a set of picture elements (Pixels), but
rather the underlying visual surface represented by the set of
pixels.
 An interpolation function can operate on this underlying
surface to generate intermediate values between the pixels.
 One set of pixels can be converted to another of a different
density or geometry.
 For example a satellite image can
be orthorectified to adjust it to
be spatially
referenced
to the earth.
Satellite Imagery
 Raw satellite imagery may be viewed but it is not directly
usable until it is processed. It needs to be orthorectified and
georeferenced.
Spot Image 4 satellite image
over part of Quebec Canada.
Geometric distortions must be
mathematically adjusted for,
and the image must be
referenced to the earth..
Coverage Types
 ISO Standard 19123 - Coverage Geometry and Functions
defines a number of different types of coverages.
Row
Column
A Quadrilateral Grid is the most common type of
coverage. The example is a Linear Scan
Quadrilateral Grid in Row then Column order.
Row
There are many other types of grid traversal methods.
The example shows a Morton order traversal. This order
is useful in that it supports non-uniform grid cells such as
in a quad-tree.
Column
Linear Scan (x, -y)
Morton Order (Z order)
Coverage Types
 There are a number of other coverage types familiar to a
user.
A grid of elevation values supporting a Digital
Elevation Model (DEM) is illustrated. A DEM is an
ordered array of ground elevations at regularly
spaced intervals.
Another way to represent an elevation surface is a
Triangular Irregular Network (TIN) coverage . A TIN is a
coverage defined by irregularly distributed nodes with
three-dimensional coordinates (x, y, and z) that are
arranged in a network of non-overlapping triangles.
Coverage Types
The point set is well used in ocean hydrography
to represent depth soundings. Closely related is
the Thiessen polygon coverage which divides an
area into a set of polygon areas by forming the
set of direct positions that are closer to that point
than to any other point in the defining set
A vector field coverage is used
for the representation of flows
such as river currents or
winds.
ISO 19115-2 Metadata Part 2
Extensions for Imagery
 The fundamental metadata standard ISO 19115:2003 –
Metadata includes metadata for coverage data in general.
 ISO 19115-2:2009 Metadata -- Part 2: Extensions for imagery
and gridded data adds to the metadata standard by defining the
schema required for describing imagery and gridded data.
 It provides information about :
 the properties of the measuring equipment used to acquire the data,
 the geometry of the measuring process employed by the equipment, and
 the production process used to digitize the raw data.
 This extension deals with metadata needed to describe the
derivation of geographic information from raw data.
ISO 19130 Metadata Part 2 Extensions
for Imagery
 ISO/TS 19130 Imagery sensor models for geopositioning
identifies the information required to determine the
relationship between the position of a remotely sensed pixel in
image coordinates and its geoposition.
 It supports exploitation of
remotely sensed images.
 It defines the metadata to be
distributed with the image to
enable user determination of
geographic position from the
observations.
Focal plane
Telescope
Mirror
Satellite
platform
Scan direction
cross track
Ground
track
 Line Scan Satellite Imager
19159 Calibration and validation of
remote sensing imagery sensors and data
 ISO/TS 19159 defines the calibration and validation of airborne
and spaceborne remote sensing imagery sensors.
 The term "calibration" refers to geometry, radiometry, and
spectral, and includes the instrument calibration in a laboratory
as well as in situ calibration methods.
 The validation methods address validation of the calibration
information.
 This standard is in several parts:
Part 1 – Optical Sensors (completed)
Part 2 – Lidar (in work)
Part 3 – Radar SAR, InSAR (planned)
Part 4 – Lidar Sonar (planned)
19163 Content components and encoding
rules for imagery and gridded data
 The standardization of an approach to handle the
multiple encoding formats for imagery and gridded
data has been a goal since 2004.
 The standard 19163 classifies imagery and regularly-spaced
gridded thematic data into types based on attribute property,
sensor type, and spatial property, and defines an encodingneutral content model for the required components for each
type of data.
 It also specifies logical data structures and the rules for encoding
the content components in the structures.
 Additional parts to this standard are planned to provide
examples on how to bind the logical data structures to selected
commonly-used physical data formats. It does not define any
new physical data formats.
ISO 19139-2 Metadata Metadata –
XML schema implementation -- Part 2:
Extensions for imagery and gridded data
 ISO 19139-2:2012 defines Geographic Metadata for imagery
and gridded data encoding.
 This complements the ISO 19139 XML schema corresponding
to the fundamental ISO 19115 Metadata standard.
 This is an XML Schema implementation derived from ISO
19115-2.
Evolution of the Standards
 All standards evolve to address additional needs and to
correct deficiencies.
 One of the Imagery, Gridded and Coverage Data standards is
in the process of revision (ISO 19130).
 This is related to the evolution of several standards.
Current
Future
Definitional
Definitional
Encoding
Evolution
ISO 19115:2003
ISO 19115-1:2014
ISO 19115-3
Metadata
Metadata fundamentals
Metadata fundamentals XML
ISO 19113:2002
ISO 19157:2013
Quality principles
Data Quality
ISO 19114:2005
Quality eval procedures
ISO 19157-2
Data Quality XML Schema
Encoding
ISO 19139:2007
Metadata XML encoding
ISO 19115-2:2009
Metadata-Imagery
ISO 19115-2 Rev
ISO 19139-2:2012
Metadata Imagery revised
Future
Metadata Imagery XML
ISO 19130-1
ISO 19130:2010
Imagery sensor models Rev
Imagery sensor models
No encoding defined
ISO 19130-2:2014
ISO 19130-3
Imagery Sensor
XML
and SensorML
SAR, lidar, sonar sensors
ISO 19159 series
Calibration Val
Coordinated XML
schema and encoding
structure